Valve devices

ABSTRACT

An aerosol valve device which is a single moulding including opposed, preferably annular, walls relatively movable from an abutting, valve closure, position to a position in which the valve device is open by applying a deforming force to the moulding, the moulding also including a dip-tube or provision for the attachment of a dip-tube and a nozzle or provision for the attachment of a nozzle.

United States Patent [72] Inventor Richard Terence Mocguire'Cooper Retemnces Cited ggga fi gs' m' UNITED STATES PATENTS l2" APPL 800.402 5 549,678 l2/l 895 Miller 222/518 X 22! Filed Feb w 9 9 1. 2. 7 2/1 35 Gl-Il'ln 222/518 X Patented g 0 l-leeter G1 al. X Prio'iy Feb. 9 968 .y 4' 968 3,i04,787 Thompson, 1!. ZZZ/402.24 X 33] Gmnmam 3.151.787 /1964 Miller 222/518 1 Potapenko at al..- X

Primary Examiner-Even C. Blunk Assistant Examiner-H. S. Lane Attorney-Pennie, Edmonds, Morton, Taylor and Adams [54] VALVE DEVICES cums Drawing ABSTRACT: An aerosol valve device which is a single mould- [52] US. Cl. 239/54], ing including opposed, preferably annular, walls relatively 222/402.24. 239/579, l 3 movable from an abutting, valve closure, position to a position [5] 1 Int. Cl. B05h 1/32 in which the valve device is open by applying a deforming Field of Search 251/353, force to the moulding, the moulding also including a dip-tube or provision for the attachment of a dip-tube and a nozzle or provision for the attachment of a nozzle.

PATENTEU AUG] 0 m SHEET 1 BF 5 PAIENTEU AUG] 0 Ian SHEET 3 (IF 5 PATENTEU mm 0 mn sum 5 OF 5 FIG. I3

VALVE DEVICES This invention relates to valve devices, such as valve devices suitable for controlling the discharge of a pressure packed product. Such a product will have been placed as a fluid for mulation under pressure in a container, the necessary pressure being derived, for example, from the vaporization of a low boiling point substance or from a compressed gas or from a compressed gas or from a combination of such means. The products, known as aerosols, may be domestic or industrial products such as paints, insecticides and polishes. It is to be understood that the term fluid" when used herein is intended to embrace not only liquids, gases and vapors but also dispersions of particulate solids in liquids, gases or vapors. In fact, the term aerosol" when used herein is to be understood to have the meaning commonly accepted by the pressure packaging industry and not the strict meaning as defined in physical chemistry.

Aerosol valve devices in current use conventionally comprise at least two relatively movable parts by which a fluid flow path through the device may be opened and closed. In addition to these parts there is normally a spring arranged to hold the fluid path in a normally closed condition. As a result, the parts are, of course, made separately and must be assembled together to produce a complete valve device.

It is an object of the present invention to avoid the separate manufacture of the parts and their assembly.

According to one aspect of the invention there is provided a valve device suitable as a discharge control mechanism for a pressure packed product and comprising a single moulding of resilient material containing a controllable fluid path through the device and having a plurality of integral portions which comprise:

relatively movable first and second portions having opposed wall portions which have an abutment position in which said path is closed;

a third portion integral with, or for securing in a fluidtight manner to, a container;

a hollow fourth portion providing a fluid outlet of said path; and

a hollow fifth portion providing a fluid outlet of said path;

a force applied to one of said fourth and fifth portions to displace that portion relatively to the third portion producing relative movement between said first and second portions relatively to move said wall portions from said abutment position to a position in which communication is provided between the interiors of said fourth and fifth portions.

According to a second aspect of the invention, there is provided a valve device comprising a single moulding of resilient material containing a controllable fluid path through the device and having a plurality of integral portions which comprise:

relatively movable first and second portions having opposed wall portions which extend along at least the major part of respective substantially coaxial annular paths and which have an abutment position in which said fluid path is closed;

and a third portion integral with, or for securing in a fluidtight manner to, a container;

a force applied to said device to displace a portion of said device relative to said third portion producing relative movement between said first and second portions relatively to move said wall portions from said abutment position to a position in which said path is open.

It is to be noted especially that the unitary construction can be readily achieved by moulding of a thermoplastic material, such as polyethylene, modified polyethylene, a polyamide such as nylon, polypropylene, ethylene/vinyl acrylate or acetate copolymer and mixtures of these materials. lt is also to be noted that differential cooling may be employed to achieve a desired final configuration. Injection moulding is particularly preferred.

By having said opposed wall portions extending for at least a major part of a closed or annular path, it is possible to utilize substantially axially symmetrical forces acting upon the opposed walls to maintain them in their abutment position, thereby to minimize leakage. Full advantage of this effect may be realized by having both of the wall portions completely annular.

In one embodiment of the invention, the relative movement of said first and second portions which opens the fluid path moves said wall portions apart. In another embodiment, this relative movement produces relative sliding motion of said wall portions thereby to uncover an aperture of the fluid path and thus to open that path. In other embodiments both actions can occur.

In the unstressed state of the valve device, the fluid path may be open or closed, although it is convenient, especially having regard to moulding technique, for the path to be normally open. A force may then be applied to the device when it is incorporated in a container, as by the way in which it is held by the container and/or by the fluid pressure within the container, to urge the opposed wall portions into their abutment position, whereby in use the fluid path is normally closed. In one such embodiment, the first portion encircles the second portion and the third portion encircles the first portion. The third portion may then be deformed, by the way in which it is held to a container and/or by the pressure within the container, to urge the first and second portions together, thereby to give a normally closed condition. The third portion might be provided by a flange portion of the device. The construction of the valve device could then be such that the fluid path may be opened by applying a force to the device to deflect the flange portion in a sense tending to restore it to its unstressed form, thereby separating the opposed wall portions. In addi tion to this action or in the alternative, a part of the first portion might buckle under a force applied to the device thereby to produce a sliding motion of the second portion relatively to the first to produce an open fluid path through the device.

It is to be noted that, by means of a flange portion as already mentioned, it is possible relatively to move the first and second portions with an angular component, thereby progressively opening and progressively closing the gap between their opposed wall portions. This effect may be utilized to achieve difierent discharge rates with different forces applied to the device. For example, the fluid path may include at least two passages each of which opens at one of the opposed wall portions but at different regions as considered in the general direction of fluid flow. Thus, one opening may be released before the other, so that a light pressure of the device opens one passage, whilst a heavier pressure opens both and gives a greater discharge rate. Such an effect can similarly be achieved in a device utilizing relative siding motion between the first and second portions.

Embodiments have been indicated in which the first portion encircles the second portion and in which, therefore, the opposed wall portions are generally cylindrical and/or frustoconical. This is not necessary, however. For example, the wall-portions may extend substantially radially of the annular path about at least the major part of which they extend. In that case, the wall portions need not be flat and might be formed so as to define between them an annular channel which will be sealed along a coaxial annular region by said wall portions when in their abutment position.

In another embodiment, the device may comprise a tubular portion defining a passageway which contains said first portion as a restriction, the second portion being at one side of said first portion and being integrally attached to the tubular portion at the other side of said first portion, the resilience of the material urging the second portion against the first portion to close the passageway in the tubular portion. Deforming pressure can then be applied to the tubular portion to produce relative movement between the first and second portions to move their annular wall portions apart to open the passageway. Such a device in its unstressed state will have its second portion at that side of the first portion at which it is secured to the tubular portion, and it will be put into an operative condition by forcing the second portion through the first portion so that, when the deforming force is released, the annular wall portion of the second portion will be held in abutment with the annular wall portion of the first portion by the force resulting from the residual deformation of the tubular portion. In a preferred form of this embodiment, the annular wall portions both taper in the same direction.

When a valve device such as has been described is in use, it is attached both to a dip-tube and to a discharge nozzle. These components may be engaged with the device after its manufacture, as by frictional engagement, or might even be formed integrally with the device in the molding process.

It is also to be noted that the device might be formed so that it can be secured to a main container body by a single mounting'member or cup. In some cases, however, such a mounting member might be used in conjunction with a further member to be interposed between the mounting member and the main container body.

For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

FIG. I is a cross section of one embodiment of a valve device;

FIG. 2 is a cross section of a portion of the valve device of FIG. 1 in its operative condition;

FIG. 3 shows a further valve device;

FIGS. 4 to 8 show methods of mounting valve devices;

FIGS. 9 to II and I3 to I show other embodiments of valve device; and

FIG. 12 shows a detail of the valve device of FIG. I1.

FIG. 1 illustrates in cross section a valve device I for the filling and for the controlled discharge of a pressurized container. The device is a single injection moulding of resilient plastics material. As illustrated, the device comprises a single piece of material, but it might include reinforcements, such as of metal, moulded in the material.

The device comprises a tubular body part 2 integral with a flange 3 which is concave as viewed from one side. The tubular body part 2 includes two annular opposed walls 4 and 5 which are defined by an annular valve seat 6 and a valve member 7 encircled by the valve seat 6. The outer annular region 8 of the flange 3 is to be gripped in a fluidtight manner by a pressurized container, as will be described hereinafter. An inlet tube 9 of the body part provides a fluid inlet tube and means for the attachment, as by frictional engagement of a dip-tube 10. A portion 11 of the body part 2 provides a fluid outlet tube and means for the attachment of a discharge nozzle 12. As will be described, the dip-tube and/or the nozzle might be moulded integrally with the device.

The valve member 7 contains a passage 13 opening at one end at the wall 5. In the illustrated unstressed state of the device the passageprovides open communication between the inlet and outlet tubes 9 and I I.

FIG. 2 illustrates the use ofa mounting member 14 which is to be bent over at I5 onto the flange 3. The member I4 is to be crimped, rolled or otherwise secured to a container or intermediate mounting member. The flange is to be so gripped that it will be held in the substantially flat condition illustrated in FIG. 2. Flattening of the flange produces a bending moment upon the valve seat 6 giving it an angular motion which urges its wall 4 into abutment with the opposed wall 5 of the valve member 7. The abutment position is illustrated in FIG. 2. It will be seen that the passage I3 is thereby sealed from the inlet tube 9. It is also to be noted that the sealing force acts in all radial directions of the device. Also pressure within the container will act on the flange to increase the sealing forces.

The flange is so secured that it may be deflected towards its original shape by a downward force applied to the inlet tube 9 or outlet tube II of the device. Such deflection produces movement of the wall 4 from the wall portion 5 and a point will be reached at which the opening of the passage I3 at the wall 5 is in communication with the inlet tube 9, thus producing the discharge under pressure of the product in the container.

It is also to be observed that the device may be attached to a container in an inverted position. Discharge can then be achieved by applying an upward force to the device, by a linkage if desired. Then the inlet tube 9 will provide the outlet and the outlet tube 11 the inlet.

A container may also be filled by way of the device, because when the valve is open, fluid flow in either direction through the device is possible.

More than one passage 13 may be provided; in addition these passages may open at the wall 5 at different heights so that, a pressure is applied to the device to open it, these passages are opened successively. Thus, a higher discharge rate is achieved with a greater deflection of the device. In addition or alternatively to a passage opening at one of the walls 4 and 5, there may be a passage opening at the upper end of the walls. Such an embodiment is illustrated in FIG. 3.

In this Figure, the valve member 7 contains a cavity I6 from which extends a vertical passage 17 opening at its lower end at the upper edge of the opposed walls 4 and S.

The outlet tube 11 is here formed as a recess to receive a stem 18 of the nozzle I2. This illustrates another way of attaching a nozzle to the device. In addition, the recess of the outlet tube has a rib to assist in retaining the nozzle stem I8.

In the embodiments of FIGS. 1 and 3, the walls 4 and 5 are completely annular and define, when separated, a completely annular groove. However, the walls 4 and 5 and the groove need only extend for the major part of an annular path, thereby to utilize the greater part of the available generally axially symmetrical sealing forces. In fact, each wall 4 and 5 may have distinct parts separated from each in the direction around its associated annular or closed loop path. In this case, there will be a corresponding number of grooves or slits defined by the walls 4 and 5.

FIG. 4 illustrates a valve device in its stressed state in combination with a metal mounting cup I4 to be crimped by deformation at 20 to the flange 3 and to be crimped or rolled at 21 to an intermediate metal member 22' itself to be crimped or rolled to a main container body 23.

FIG. 5 illustrates a valve device crimped to a mounting member I4 to be crimped or rolled or otherwise secured directly to the main container body 23. An orifice-to-face sealing action in the device is to be especially noted.

FIG. 6 shows a valve device in combination with the mounting member or neck I4 of a S.A.F.C.A. type can. The flange 3 is to rest on folds 24 of the neck and is to be covered by a plate 25 over which the neck is to be crimped.

FIG. 7 shows a valve device attached directly to the top of a glass or plastics container 23 by a sealing cap I4 engaged about the neck of the container.

FIG. 8 shows an application in which the valve device is integral with a container 23 containing a fluid under pressure. The flange 3 of the device constitutes the upper surface of the container. The pressure within the container will tend to flatten the flange 3 and seal the valve. The container may be moulded in two parts, a lower part and an upper part integral with the valve device.

FIG. 9 illustrates a valve device similar in appearance to the devices of FIGS. I to 8. As with those devices, the flange 3 is to be flattened to urge the walls 4 and 5 together to seal the inlet tube 9 from the outlet tube II. However, the flange 3 is directly adjacent only the lower part of the valve seat 6, leaving an upper cylindrical region 6' of the valve seat free. Consequently, downward pressure on the nozzle stern I8 will buckle the region 6' to produce a downward movement of the valve member relatively to the flange. A point will be reached at which the opening of passage I3 emerges below the wall 4. Accordingly, the flange may be relatively rigid or could be held so that it does not flex appreciably. However, it could alternatively be allowed to flex so that the device operates with a combination of the action of the previously described devices and the action of the downward movement of the valve member 7 relative to the flange. Indeed it may be found in practice that the latter action occurs to some extent in the previously described valve devices.

FIG. 10 illustrates a further embodiment in which the valve seat 6 and the valve member 7 define between them an annular channel 26 which is at all times open to the interior of the outlet tube 11. The flange 3 of the device is to be gripped by to the mounting member I4 which is to be crimped or rolled directly to the main body of a container without any intermediate member. A dip-tube I is to engage about the inlet tube 9 which has a projection to assist in retaining the diptube.

The pressure within the container acts on the device to urge the valve seat 6 into abutment with the second portion 7 to seal the annular channel along an annular path. The pressure of the dip-tube on the inlet valve 9 will also provide sealing pressure. In addition sealing force may be provided by the gripping of the flange 3 by the mounting member, as in previous embodiments. Downward pressure on the outlet tube 11 will deflect the flange 3 and thus apply radially outward forces on the valve seat 6 to open the fluid path through the device.

FIG. 1 1 illustrates a further embodiment in which the valve seat 6 and the valve member 7 define between them an annular channel 26. In this case, both of the opposed walls 4 and extend generally radially. They may be urged into abutment to seal the channel 26 from the dip-tube by the pressure within the container. This may be assisted by the force applied by the mounting member I4 to the flange 3 and/or by the dip-tube 10. Figure 12 illustrates how a projection can be provided on one of the walls 4 and 5 to assist sealing.

It is also to be noted that the inlet tube of earlier embodiments is replaced by another provision 'for attaching the diptube to the device; in this case there is the cylindrical outer surface of the valve seat 6, which may be provided with a projection as illustrated to assist in retaining the dip-tube.

FIG. 13 illustrates another form of valve device in its unstressed state. This injection moulded device has a tubular body part 2 containing a restriction which constitutes the valve seat 6 and which provides an annular wall 4 which tapers. Attached within the tubular body part 2 is a valve member 7 having a recess 27 and an annular wall 5 tapering in the same direction as the wall 4. A further annular projection 28 is provided within the body part 2. A flange 3 is provided to enable the device to be secured to a container. As in all other embodiments, the flange might be moulded integrally with a container or a container section.

FIG. I4 illustrates a valve device such as that illustrated in FIG. 13 in its operative state. The valve member 7 has been forced through the restriction or valve seat 6 thereby buckling the tubular wall 29 between the seat 6 and the outlet tube I1. The stress in the wall 29 urges the annular walls 4 and 5 into abutment to seal the passageway in the tubular body part 2. Pressure on the outlet tube 11 further buckles the wall 29 and displaces the valve member 7 downwardly to open the passageway, which is closed when that pressure is released. The restriction 28 limits the downward movement of the valve member 7.

The device of FIG. I4 is shown with an outlet tube II adapted to receive the stem 18 of a nozzle 12, whereas in FIG. 11 the tube 11 is adapted to engage directly in a nozzle I2.

FIG. illustrates an embodiment similar to those of FIGS. I3 and I4, but in which the nozzle 12 is moulded integrally with the valve device. As moulded, the nozzle I2 is open at its upper end to receive a closure plug 30.

The embodiments of FIGS. 13 to I5 may be mounted by means of their flanges 3 in the way described for earlier devices. Accordingly, the flanges may be provided with at least one groove and/or rib to assist in their location.

However, the flange may be omitted and the resulting cylindrical outer surface of the device may be held directly by a container or mounting member. To assist in securing the valve device, the cylindrical outer surface may have at least one groove and/or'rib. This could also be the casein a'device such as is illustrated in FIG. 9.

I claim: v

I. A valve device for controlling the'passage of a medium under pressure and which is a single moulding composed of:

a body part which in the unstressed state of said device as moulded has one end region formed as an outlet tube and an opposite end region formed as a tubular portion for the attachment of a dip-tube;

a valve member having a first annularsea'ling surface;

an annular valve seat defined by said body part and having a second annular sealing surface coaxial with but spaced from said first annular sealing surface in said valve device as moulded to provide an open condition of said device in its unstressed state;

a linkage part integrally joining said valve member to said body part and at least in part defining a nonannular passage to provide for flow of said medium past said valve member to said outlet tube; and an annular spring part integrally joined to said valve seat and having a first disposition in which said device is moulded in said open condition and a second, deformed, disposition in which said stress in said spnng part holds said sealing surfaces in abutment to afford a normally closed condition of said device.

2. A valve device as claimed in claim I, wherein said spring part is an annular portion of said body part between said outlet tube and said valve seat.

3. A valve device as claimed in claim I, wherein said valve seat encircles said valve member in the unstressed state of said device as moulded and said annular spring part is a flange integrally encircling said body part and having said second, deformed, disposition in which stressing said flange holds said sealing surfaces in abutment.

4. A valve device as claimed in claim I, wherein at least a major portion of an outlet spray nozzle is integrally moulded to said outlet tube.

5. A valve device for controlling the passage of a medium under pressure and which is a single moulding comprising a valve member defining a first annular sealing surface;

an annular valve seat defining a second annular sealing surface facing but spaced from said first annular sealing surface in said device as moulded to provide a through-flow path of said device;

a linkage part integrally joining said valve member and said valve seat; and

an annular spring part integrally connected substantially coaxially with said valve seat and having a first disposition in which said device is fabricated in an open condition and a second, deformed, position in which said sealing surfaces are held in abutment to afford a normally closed condition of said device.

6. A valve device as claimed in claim 5, wherein said valve seat encircles said valve member in said device as moulded to define therebetween an annular passage.

7. A valve device as claimed in claim 6, and comprising an integral, hollow, outlet portion with which said annular passage communicates and is substantially coaxial. v

8. A valve device as claimed in claim 5 and comprising a resilient mounting flange connected integrally to said valve seat and defining said annular spring part which is deformable by a dishing action between said first and second dispositions.

9. A valve device as claimed in claim 5 and comprising a tubular body part defining a hollow outlet portion,.said flange being integrally connected around said body partQsaid valve seat being defined by an internal wall portion of said body part, and said valve device being secured within said body part by said linkage part.

I0. A valve device as claimed in claim 9, wherein said linkage part at least partly defines a passage opening into said hol'- low outlet portion and extending generally parallel to the axes of said first and second annular sealing surfaces.

11. A valve device as claimed in claim 5, wherein said valve seat surrounds said valve member and wherein a resilient mounting flange encircles a part of said valve seat leaving a cylindrical part of said valve seat free to buckle under the action of a force applied to said valve member thereby to produce a sliding movement of said valve member relative to said valve seat to put said device into a stressed open condition.

12. A valve device as claimed in claim and comprising a resilient mounting flange defining said annular spring part which is deformable by a dishing action between said first and second dispositions and can adopt a further stressed third disposition in which said sealing surfaces are relatively angularly displaced from said normally closed condition.

13. A valve device as claimed in claim 12, wherein said linkage part defines a passage opening at that end of said sealing surfaces adjacent said linkage part.

14. A valve device as claimed in claim 5, wherein at least one of said valve seat, said valve device and said linkage part defines a passage which opens at one of said sealing surfaces.

15. A valve device as claimed in claim 14 and comprising more than one said passage opening at one of said sealing surfaces and the openings of these passages being at different regions along said one sealing surface as considered in the axial direction of said one sealing surface.

16. A valve as claimed in claim 5 and comprising, as moulded, a generally tubular body part defining an outlet passage at one end, an inlet passage at the opposite end and said valve seat between said ends.

17. A valve device comprising a single moulding of resilient plastics material containing a controllable fluid flow path and having a plurality of integral portions which comprise, in the unstressed state of said device, a generally tubular part defining a passageway, a valve seat formed as a restriction in said passageway, a valve member integrally attached within said tubular part at one side of said restriction, and an annular spring portion of said tubular part which integrally joins said valve seat to said valve member and being deformable between an unstressed first disposition in which said device is moulded with said passageway open and said valve member at said one side of said restriction, a stressed second disposition in which said valve member is at the opposite side of said restriction and is held in abutment with said valve seat to close said passageway, and a stressed third disposition in which said valve member is displaced from said valve seat to open said passageway.

18. A valve device as claimed in claim 17 and wherein said moulding includes a linkage part integrally joining said valve member to said body part and defining a passage substantially codirectional with said passageway and providing a communication between opposite ends of said passageway in said first and third dispositions.

mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION August 10, 1971 Patent: No. 3, 598,324 Dated Inventor) Richard Terence Macquire-Cooper It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 1.8, change "valve" to -tube-.

Column 6 (claim 9) line 1, chaage 5 to 8 (Claim 8 was 65 and claim 9 was 66 depending from claim 65) Signed and sealed this 11th day of July 1972.

( SEAL) Attest:

EDWARD M.FLEICIIER,JR. ROBERT GUITSCHALK Commissioner of Patents Attesting Officer 

1. A valve device for controlling the passage of a medium under pressure and which is a single moulding composed of: a body part which in the unstressed state of said device as moulded has one end region formed as an outlet tube and an opposite end region formed as a tubular portion for the attachment of a dip-tube; a valve member having a first annular sealing surface; an annular valve seat defined by said body part and having a second annular sealing surface coaxial with but spaced from said first annular sealing surface in said valve device as moulded to provide an open condition of said device in its unstressed state; a linkage part integrally joining said valve member to said body part and at least in part defining a nonannular passage to provide for flow of said medium past said valve member to said outlet tube; and an annular spring part integrally joined to said valve seat and having a first disposition in which said device is moulded in said open condition and a second, deformed, disposition in which said stress in said spring part holds said sealing surfaces in abutment to afford a normally closed condition of said device.
 2. A valve device as claimed in claim 1, wherein said spring part is an annular portion of said body part between said outlet tube and said valve seat.
 3. A valve device as claimed in claim 1, wherein said valve seat encircles said valve member in the unstressed state of said device as moulded and said annular spring part is a flange integrally encircling said body part and having said second, deformed, disposition in which stressing said flange holds said sealing surfaces in abutment.
 4. A valve device as claimed in claim 1, wherein at least a major portion of an outlet spray nozzle is integrally moulded to said outlet tube.
 5. A valve device for controlling the passage of a medium under pressure and whiCh is a single moulding comprising a valve member defining a first annular sealing surface; an annular valve seat defining a second annular sealing surface facing but spaced from said first annular sealing surface in said device as moulded to provide a through-flow path of said device; a linkage part integrally joining said valve member and said valve seat; and an annular spring part integrally connected substantially coaxially with said valve seat and having a first disposition in which said device is fabricated in an open condition and a second, deformed, position in which said sealing surfaces are held in abutment to afford a normally closed condition of said device.
 6. A valve device as claimed in claim 5, wherein said valve seat encircles said valve member in said device as moulded to define therebetween an annular passage.
 7. A valve device as claimed in claim 6, and comprising an integral, hollow, outlet portion with which said annular passage communicates and is substantially coaxial.
 8. A valve device as claimed in claim 5 and comprising a resilient mounting flange connected integrally to said valve seat and defining said annular spring part which is deformable by a dishing action between said first and second dispositions.
 9. A valve device as claimed in claim 5 and comprising a tubular body part defining a hollow outlet portion, said flange being integrally connected around said body part, said valve seat being defined by an internal wall portion of said body part, and said valve device being secured within said body part by said linkage part.
 10. A valve device as claimed in claim 9, wherein said linkage part at least partly defines a passage opening into said hollow outlet portion and extending generally parallel to the axes of said first and second annular sealing surfaces.
 11. A valve device as claimed in claim 5, wherein said valve seat surrounds said valve member and wherein a resilient mounting flange encircles a part of said valve seat leaving a cylindrical part of said valve seat free to buckle under the action of a force applied to said valve member thereby to produce a sliding movement of said valve member relative to said valve seat to put said device into a stressed open condition.
 12. A valve device as claimed in claim 5 and comprising a resilient mounting flange defining said annular spring part which is deformable by a dishing action between said first and second dispositions and can adopt a further stressed third disposition in which said sealing surfaces are relatively angularly displaced from said normally closed condition.
 13. A valve device as claimed in claim 12, wherein said linkage part defines a passage opening at that end of said sealing surfaces adjacent said linkage part.
 14. A valve device as claimed in claim 5, wherein at least one of said valve seat, said valve device and said linkage part defines a passage which opens at one of said sealing surfaces.
 15. A valve device as claimed in claim 14 and comprising more than one said passage opening at one of said sealing surfaces and the openings of these passages being at different regions along said one sealing surface as considered in the axial direction of said one sealing surface.
 16. A valve as claimed in claim 5 and comprising, as moulded, a generally tubular body part defining an outlet passage at one end, an inlet passage at the opposite end and said valve seat between said ends.
 17. A valve device comprising a single moulding of resilient plastics material containing a controllable fluid flow path and having a plurality of integral portions which comprise, in the unstressed state of said device, a generally tubular part defining a passageway, a valve seat formed as a restriction in said passageway, a valve member integrally attached within said tubular part at one side of said restriction, and an annular spring portion of said tubular part which integrally joins said valve seat to said valve member and being deformable betweeN an unstressed first disposition in which said device is moulded with said passageway open and said valve member at said one side of said restriction, a stressed second disposition in which said valve member is at the opposite side of said restriction and is held in abutment with said valve seat to close said passageway, and a stressed third disposition in which said valve member is displaced from said valve seat to open said passageway.
 18. A valve device as claimed in claim 17 and wherein said moulding includes a linkage part integrally joining said valve member to said body part and defining a passage substantially codirectional with said passageway and providing a communication between opposite ends of said passageway in said first and third dispositions. 